摘要
水铝钙石(Hydrocalumite)是一种阴离子黏土,又称"弗里德尔盐"(Friedel’s Salt),属于层状双金属氢氧化物(LDHs),可通过多种低成本方法人工合成.水铝钙石的层间阴离子具有可交换性,且在一定温度范围内焙烧时所获产物在水溶液中具有层状结构可恢复性,因此在水污染和固体废物处理领域有很大应用价值,已被用于水中B(OH)4-、SeO24-、CrO24-、MoO24-、Zn2+等无机组分和十二烷基硫酸钠(SDS)、烷基苯磺酸钠(SDBS)、甲基橙(MO)、酸性大红(GR)等有机组分的去除实验研究,以及粉煤灰等典型固体废物在填埋前的预处理研究.水铝钙石类阴离子黏土对水中有害组分的去除效果受到离子种类和性质、溶液pH、去除产物溶度积常数等多种因素的影响,所涉及去除机理包括离子交换、溶解-沉淀、表面吸附等.当前利用水铝钙石去除水污染的研究基本局限于实验室研究阶段,并在严格控制的实验条件下进行,因而今后应加强其处理实际受污染水体和原生劣质水的实验研究,并尝试作为填充材料在可渗透性反应墙(PRB)等水污染原位处理装置中加以应用.
Hydrocalumite,also known as Friedel＇s salt,belongs to the group of layered double hydroxides（LDHs）.and can be synthesized via a variety of low-cost techniques.Hydrocalumite has exchangeable interlayer anions.Its calcination product obtained within a specific temperature range is capable of recovering its original structure during subsequent exposure to air or water due to so-called ＂structural memory effect＂,which endow hydrocalumite with a huge potential in a wide range of applications,e.g.treatment of wastewater,contaminated water,and solid wastes.Hydrocalumite has been used to remove some hazardous inorganic ions（B（OH） 4-,SeO24-,CrO24-,MoO24-,Zn2 ＋） and organic constituents（SDS,SDBS,MO,GR） from aqueous solution.It has also been used in fly ash pretreatment,resulting in the concentration reduction of some undesired oxyanions in ash leachate.The efficiency of water treatment by hydrocalumite is controlled by several factors,such as characteristics of target ions,pH values in solution,and solubility product constants（Ksp） for reaction products.Mechanisms responsible for hydrocalumite＇s uptake of solution contaminants,including anion exchange,dissolution-reprecipitation,and surface adsorption,have been investigated systematically.Nevertheless,the anion uptake capacity of hydrocalumite was basically tested via lab-based studies that were mostly carried out under designed experimental conditions.It is vitally important to try to treat actual contaminated water and naturally occurring poor-quality water with hydrocalumite in the future.Hydrocalumite is a promising material to be used in in-situ treatment of water contamination as the loading material of permeable reactive barriers（PRB）.
出处
《环境化学》
CAS
CSCD
北大核心
2013年第8期1571-1579,共9页
Environmental Chemistry
基金
中央高校基本科研业务费专项资金(CUG120505
CUG120113)资助
关键词
水铝钙石
共沉淀
水处理
溶度积常数
阴离子交换
结构记忆效应
hydrocalumite
co-precipitation
water treatment
solubility product
anion exchange
structure memory effect
